The composition and structure of cometary dust particles and their diversity pose many unresolved questions. We aim to better understand the interaction of cometary dust with electromagnetic radiation and to infer dust properties from measured radiation. Electromagnetic radiation that we receive from cometary dust is either scattered sunlight, typically at visible wavelengths, or thermally emitted radiation, typically in the infrared.
We analyse measurements of the scattered light, in particular its degree of linear polarisation, and the thermal emission by dust, their dependency on wavelength and on the viewing direction (phase angle).
To interpret and connect measurements of light scattering and thermal emission by cosmic dust particles and planetary surfaces covered by such particles (regoliths), we develop novel computational methods to consistently describe and solve electromagnetic wave scattering, absorption, and propagation in a dense discrete random medium at wavelengths from the ultraviolet to the thermal infrared.
We also develop thermophysical models by coupling the radiative heat transport with the conductive heat and gas transport, and the phase change physics. This allows us to study the time evolution of cometary dust particles after being ejected from the nucleus as well as the processes driving the activity.
